Lee Neck Sizing Die
- Thread starter Wendyj
- Start date
The Lee collet neck sizing die is one of the clever innovations of Lee that no one else has.
It almost always results in less neck tension than a FL die or regular neck sizing dies. It CAN be tuned to result in the same neck tension/bullet pull of regular dies.
This is done by reducing the diameter of the mandrel that the neck is pushed against/around by the collet fingers. Simply chuck it in a drill motor, hold some emery paper against it as it's spun. It's very helpful to have a micrometer that reads out in .0001 increments so you don't go too far. Usually .001 is all you have to take off to get better neck tension.
Before I learned the above trick,(I didn't invent that trick,) I actually broke the main pivot pin on my Bonanza,(now forster), co-ax press. Thinking that the brass had to be pressed harder against the mandrel to achieve the needed extra neck tension. I should send the co-ax to forster, they said they could fix it, and add the universal primer seater,(mine requires the Bonanza special shell holders).
The Lee collet neck sizing die just plain works. Just learn how to use it.
It almost always results in less neck tension than a FL die or regular neck sizing dies. It CAN be tuned to result in the same neck tension/bullet pull of regular dies.
This is done by reducing the diameter of the mandrel that the neck is pushed against/around by the collet fingers. Simply chuck it in a drill motor, hold some emery paper against it as it's spun. It's very helpful to have a micrometer that reads out in .0001 increments so you don't go too far. Usually .001 is all you have to take off to get better neck tension.
Before I learned the above trick,(I didn't invent that trick,) I actually broke the main pivot pin on my Bonanza,(now forster), co-ax press. Thinking that the brass had to be pressed harder against the mandrel to achieve the needed extra neck tension. I should send the co-ax to forster, they said they could fix it, and add the universal primer seater,(mine requires the Bonanza special shell holders).
The Lee collet neck sizing die just plain works. Just learn how to use it.
DAVID NANCARROW
New member
I have neck sized 308 cases with my Rockchucker IV and the Lee collet die, and set it up 3 turns before cam over could occur on the press.
As others have posted, it doesn't take a lot of strength to size the neck with this product, but some of the die mandrels might need a bit of polishing in order to get enough neck tension. Mine did, and I used a drill chuck and 0000 steel wool to polish it.
I liked the neck tension that my FL die gives, so I measured the button and smoothed the mandrel down to the same diameter.
It is nice to be able to size without lube, and I can feel the collet size the neck.
The issue I find with a neck sizing die only comes about when I fire full powered loads through my rifle. The collet die of course does nothing to set the shoulder back, nor is it designed to-the reloads are more difficult to chamber. Backing the powder charge off a couple of grains and the cases work nicely.
I have a couple of pet loads which show their best accuracy at or very near maximum, and for those I have to use the full length sizing die in order to get smooth function from the magazine.
As others have posted, it doesn't take a lot of strength to size the neck with this product, but some of the die mandrels might need a bit of polishing in order to get enough neck tension. Mine did, and I used a drill chuck and 0000 steel wool to polish it.
I liked the neck tension that my FL die gives, so I measured the button and smoothed the mandrel down to the same diameter.
It is nice to be able to size without lube, and I can feel the collet size the neck.
The issue I find with a neck sizing die only comes about when I fire full powered loads through my rifle. The collet die of course does nothing to set the shoulder back, nor is it designed to-the reloads are more difficult to chamber. Backing the powder charge off a couple of grains and the cases work nicely.
I have a couple of pet loads which show their best accuracy at or very near maximum, and for those I have to use the full length sizing die in order to get smooth function from the magazine.
I finally got it to work by turning the brass a few times as I pressed it. Still doesn't feel tight as fls die when seating a bullet. I used the Lee crimp die and gave 3 I done a small crimp. They shoot and brass seems consistent now. I think I will try the steel wool and take the mandrel down some. I like no lube and doesn't measure to need trimming. Fits snug with bolt but not too snug. I just want some more pressure on the bullet. This may be ok to just go shoot but I think I'll fl size for hunting season. My opinion of it so far.
603Country
New member
It could be that the neck is holding the bullet well enough, but that the neck tension may just be less than you are used to. As long as there's enough tension, you are good to go. And, one thing I like about the die is that neck tension seems to be much more consistent, which leads to accuracy.
If the cases have been shot a lot and need annealing, then it is possible (and maybe likely) that the brass won't be sized enough with the Lee Collet Die. I don't know this for a fact, but have considered the possibililty.
I use a Redding Body Die to bump shoulders back when that becomes necessary. And a Redding FL bushing die, without the bushing, will also bump the shoulders like a Body Die does.
If the cases have been shot a lot and need annealing, then it is possible (and maybe likely) that the brass won't be sized enough with the Lee Collet Die. I don't know this for a fact, but have considered the possibililty.
I use a Redding Body Die to bump shoulders back when that becomes necessary. And a Redding FL bushing die, without the bushing, will also bump the shoulders like a Body Die does.
Wendy,
This die is famous for requiring the user to go through a learning curve.
Lee advises putting about 35 lbs of force on the handle. Different presses have different mechanical advantages, but if yours is a Challenger press, then that number should be about right for it. To get the feel of that pressure, stand on a bathroom scale and push down until the scale shows 35 lbs less. I've done this and the scale is very shaky in its reading when I do, but I just look for the average to be about the right number. Unfortunately, to do that technique, I find some scales are hard to put where I can read them well. Having to look over my Budweiser tumor to see the scale probably doesn't help. But another way is to pull the knob off the press handle and press it down on the bathroom scale to get a feel for what 35 lbs of force is like. You could also pull the handle with a fish scale, but be aware the knob can fly off suddenly.
The object of all that trouble is to see if the specified weight is adequate to size your cases or not. Assuming not, you may need a mandrel adjustment either of your own or done by the factory. To find out, you want to try a couple of other things.
First, let's measure whether or not you may need it. Brass is slightly springy. You can figure between 1/2 and 1 thousandth of neck spring-back after squeezing the brass against the mandrel, so you want the mandrel to be that much smaller than the finished neck ID you want. The finished neck ID should probably be about -0.0020" smaller than the bullet for a fairly firm grip on it. You can tell what you are getting now by measuring the outside of the neck before seating a bullet, and then again over top of the widest part of the bullet to see how much it made the neck grow. But the bottom line is you likely need the mandrel 0.0025"-0.0030" smaller than the diameter of the bullet.
You can make a rough check with a digital caliper by zeroing it on a bullet, then measuring the mandrel where the bullet is squeezed against it. Calipers aren't very precise for an adjustment, but a difference measurement like that is generally pretty close.
If you are going to narrow the mandrel with wet/dry sandpaper, as described earlier, then you probably want to have a thimble OD micrometer with a 0.0001" resolution vernier scale, rather than a caliper. It's much easier to see and control what you are doing with one. For measuring the difference between a bullet and a mandrel, you only need an inexpensive one. Harbor Freight has one for $20 and Enco has one for about $15, though that doesn't include P&H. Either is adequate. If you aren't familiar with reading vernier scales, then the least expensive digital micrometer is about $35 from Harbor Freight. The main thing to remember about these tools is, despite their appearance, they are not C-clamps and should never be tightened hard on anything to avoid ruining them. A delicate touch is needed.
Second, as 603Country mentioned, if the brass has been reloaded several times before, the neck may be getting work-hardened from the repeated exercise. This can make it even more springy. To fix that you need to stress-relieve the neck. This is also called partial annealing, though most shooters just call it annealing, even though that's not strictly technically correct.
You want to try this out rather than go to the trouble of doing all your cases if you are not sure you need to do it. So pick just one case that is like the others you've had trouble with and has the same load history. Light a candle and, holding the case by its head, roll it back and forth between your thumb and index finger while letting the flame play over the neck and shoulder of the case. The soot will tell you if you are heating it evenly all around, which you want to.
When enough heat has got back to the head that it is starting to get too warm to hold onto, set the case down. Some folks slap it on a wet towel to cool it faster and get the soot off, but you can just leave it sitting upright to cool. The candle flame is cool enough that it eliminates any chance of overheating the neck and getting it too soft and weak. A temperature you can just hang onto is not nearly hot enough to anneal the head, which you must avoid doing, for safety reasons. It's a slow method, but a very safe one.
After annealing, try the case in the Lee die and see if it does any better than the others. If so, the others need annealing, too. They won't need it every time.
This die is famous for requiring the user to go through a learning curve.
Lee advises putting about 35 lbs of force on the handle. Different presses have different mechanical advantages, but if yours is a Challenger press, then that number should be about right for it. To get the feel of that pressure, stand on a bathroom scale and push down until the scale shows 35 lbs less. I've done this and the scale is very shaky in its reading when I do, but I just look for the average to be about the right number. Unfortunately, to do that technique, I find some scales are hard to put where I can read them well. Having to look over my Budweiser tumor to see the scale probably doesn't help. But another way is to pull the knob off the press handle and press it down on the bathroom scale to get a feel for what 35 lbs of force is like. You could also pull the handle with a fish scale, but be aware the knob can fly off suddenly.
The object of all that trouble is to see if the specified weight is adequate to size your cases or not. Assuming not, you may need a mandrel adjustment either of your own or done by the factory. To find out, you want to try a couple of other things.
First, let's measure whether or not you may need it. Brass is slightly springy. You can figure between 1/2 and 1 thousandth of neck spring-back after squeezing the brass against the mandrel, so you want the mandrel to be that much smaller than the finished neck ID you want. The finished neck ID should probably be about -0.0020" smaller than the bullet for a fairly firm grip on it. You can tell what you are getting now by measuring the outside of the neck before seating a bullet, and then again over top of the widest part of the bullet to see how much it made the neck grow. But the bottom line is you likely need the mandrel 0.0025"-0.0030" smaller than the diameter of the bullet.
You can make a rough check with a digital caliper by zeroing it on a bullet, then measuring the mandrel where the bullet is squeezed against it. Calipers aren't very precise for an adjustment, but a difference measurement like that is generally pretty close.
If you are going to narrow the mandrel with wet/dry sandpaper, as described earlier, then you probably want to have a thimble OD micrometer with a 0.0001" resolution vernier scale, rather than a caliper. It's much easier to see and control what you are doing with one. For measuring the difference between a bullet and a mandrel, you only need an inexpensive one. Harbor Freight has one for $20 and Enco has one for about $15, though that doesn't include P&H. Either is adequate. If you aren't familiar with reading vernier scales, then the least expensive digital micrometer is about $35 from Harbor Freight. The main thing to remember about these tools is, despite their appearance, they are not C-clamps and should never be tightened hard on anything to avoid ruining them. A delicate touch is needed.
Second, as 603Country mentioned, if the brass has been reloaded several times before, the neck may be getting work-hardened from the repeated exercise. This can make it even more springy. To fix that you need to stress-relieve the neck. This is also called partial annealing, though most shooters just call it annealing, even though that's not strictly technically correct.
You want to try this out rather than go to the trouble of doing all your cases if you are not sure you need to do it. So pick just one case that is like the others you've had trouble with and has the same load history. Light a candle and, holding the case by its head, roll it back and forth between your thumb and index finger while letting the flame play over the neck and shoulder of the case. The soot will tell you if you are heating it evenly all around, which you want to.
When enough heat has got back to the head that it is starting to get too warm to hold onto, set the case down. Some folks slap it on a wet towel to cool it faster and get the soot off, but you can just leave it sitting upright to cool. The candle flame is cool enough that it eliminates any chance of overheating the neck and getting it too soft and weak. A temperature you can just hang onto is not nearly hot enough to anneal the head, which you must avoid doing, for safety reasons. It's a slow method, but a very safe one.
After annealing, try the case in the Lee die and see if it does any better than the others. If so, the others need annealing, too. They won't need it every time.
WVMountaineer
New member
Unclenick, you 'da man.
There is a YOUTUBE video by a member of another forum, Twoshooter or something like that. He claims he heats the neck and holds the case head in his hand. He has a cute little saying, he says when the case head gets too hot to hold it is done. His video starts with him holding the case head and then!? Suddenly and without warning: The video stops and starts over, the case head and hand are no longer visible.
Then there is the candle, that story always starts with "I have done this for years". same thing, there is the claim the case is held in the hand while the neck is heated and I have always ask: "How long does it take to heat the neck of a case to 650 degree +/- a few?", with a candle.
It just seems there are so many violators that ignore the rules of annealing.
Wendyj, looks to me like your are going to be doing some more shopping, bushing dies, body dies
F. Guffey
That video sound hilarious. If you find a link, please put it up.
The genesis of the candle approach, for me, is that I first saw it in Fred Barker's article, Case Neck Annealing: Metallurgy & Two Easy Methods (Precision Shooting, July 1996, p.p. 90-92). He runs through the usually methods and their flaws, then cites a William Dresser article in TAR (September, 1962) as the first one based on metallurgical principles rather than on just making case necks red. Dresser used 700°F Tempilaq and a propane torch, instead. Dresser pointed out cases heated to red are so weakened and coarse grained that they can split in as few as two or three reloadings.
Barker further mentions the June, 1972 issue of Shooting Times, in which the late Bob Milek described the problems he and the late Steve Herrett initially had in necking .44 Mag cases to .30 caliber. Again, the red heat, followed by splitting during forming. It wasn't until Bob figured Steve's torch-to-red approach was too hot, and began the dip-in-graphite, then hold in 750° molten lead alloy until too-hot-to-keep-hanging-on approach, that this problem was cleared up.
At any rate, Barker recommended both the candle and the lead dip, using a temperature range of 725-750°F for the dip, and holding the head until you can't. I think the idea, from Dresser, is that 700°F is about minimum for the time frames involved. With a faster propane torch, by the time you see 650° Tempilaq change, the case will overshoot to 700°F pretty reliably, which I believe is where that number comes from. But whether with 650°F or 700°F Tempilaq, either way you are stuck having to clean Tempilaq off, which what Barker wanted to avoid.
The temperatures are all time-dependent. If you can hold the temperature for an hour, have more time, say, in an oven, then you only need about 570° to complete stress relief. As you go faster, you need to get hotter for the stress to clear out of the neck before the head gets too hot. I think the military uses a still higher temperature, but the production is relatively high speed, so the time is even shorter.
The genesis of the candle approach, for me, is that I first saw it in Fred Barker's article, Case Neck Annealing: Metallurgy & Two Easy Methods (Precision Shooting, July 1996, p.p. 90-92). He runs through the usually methods and their flaws, then cites a William Dresser article in TAR (September, 1962) as the first one based on metallurgical principles rather than on just making case necks red. Dresser used 700°F Tempilaq and a propane torch, instead. Dresser pointed out cases heated to red are so weakened and coarse grained that they can split in as few as two or three reloadings.
Barker further mentions the June, 1972 issue of Shooting Times, in which the late Bob Milek described the problems he and the late Steve Herrett initially had in necking .44 Mag cases to .30 caliber. Again, the red heat, followed by splitting during forming. It wasn't until Bob figured Steve's torch-to-red approach was too hot, and began the dip-in-graphite, then hold in 750° molten lead alloy until too-hot-to-keep-hanging-on approach, that this problem was cleared up.
At any rate, Barker recommended both the candle and the lead dip, using a temperature range of 725-750°F for the dip, and holding the head until you can't. I think the idea, from Dresser, is that 700°F is about minimum for the time frames involved. With a faster propane torch, by the time you see 650° Tempilaq change, the case will overshoot to 700°F pretty reliably, which I believe is where that number comes from. But whether with 650°F or 700°F Tempilaq, either way you are stuck having to clean Tempilaq off, which what Barker wanted to avoid.
The temperatures are all time-dependent. If you can hold the temperature for an hour, have more time, say, in an oven, then you only need about 570° to complete stress relief. As you go faster, you need to get hotter for the stress to clear out of the neck before the head gets too hot. I think the military uses a still higher temperature, but the production is relatively high speed, so the time is even shorter.
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Looks like I've got a lot to learn. Lol. I have only been doing this a few months but it seems to take the edge off of a hard day. I have a torch but don't think I'll be heating my brass until fingers burn. Time to buy some more. These are probably in 10 on some and twenty on the others the times I've reloaded. Brass still looks good. Found a few that primed a little too easy on the press. Trashed those.
The Hornady brass seems weak in the primer pockets. Sides shave on some and have to trim little pieces of shavings with pocket knife. Primer seat okay in them. Nosler brass doesn't do this at all. I don't want to spend a fortune on brass but would like to buy another 100. Lapua is really fond of theirs at $79.00 for a box. Any recommendations
The Hornady brass seems weak in the primer pockets. Sides shave on some and have to trim little pieces of shavings with pocket knife. Primer seat okay in them. Nosler brass doesn't do this at all. I don't want to spend a fortune on brass but would like to buy another 100. Lapua is really fond of theirs at $79.00 for a box. Any recommendations
603Country
New member
Heck, Lapua seems cheap compared to Norma. Pretty much any brass will work just fine for you (and me), but I used to spend a lot time weighing and prepping the Remington and Winchester, and I got tired of doing that work. So, I just started buying Lapua, Norma, and Nosler, since prep generally isn't needed at all. But if you don't mind the prep, once I did all that to Remington and Winchester it shot as good as anything else. Truth be told, most of the brass I'm using now in the 220 and the 270 are prepped Winchester and Remington. When they wear out, which will take a while, I have the new stuff waiting.
DAVID NANCARROW
New member
I would (and just did) buy some more Lapua brass. Might seem pricey but its good stuff.
603Country
New member
The Norma is good stuff and as good as Lapua. Nosler is right there with them, but in my experience it seems a bit softer and less durable. That's just what I think, which doesn't make it a fact. I still have some Nosler, but at their price I'll just stay with Norma and Lapua. Over the years, I have more use experience with Norma than I do with Lapua, and the Norma will last a long time if you don't shoot at redline max. I used Norma in my 220 Swift and some near max loads and it lasted for (and this is only a guess) at least 15 reloads. Maybe more. I retired it before the primer pockets got loose, but I kept it for possible future use if I run out of newer brass. For the record, with that particular Norma brass, I partial resized it every time. The cases eventually got snug in the chambers, but back then that didn't tell me anything, so I just reloaded and shot it. That old Swift would, even with those snug loads, which aren't supposed to be accurate, put 5 rounds into very small groups. Admittedly, the rifle had been tuned up by a high level gunsmith, who installed a terrific Douglas barrel, so it was supposed to shoot good.
Anyway...I regard Norma and Lapua as equals, for my use.
Anyway...I regard Norma and Lapua as equals, for my use.
Anyone familiar with long range match brass. Picked up 53 rounds today for $10.00 from a guy that shoots longe range competition. Doesn't reload. Has buddy reload one time and never uses again. Supposed to bring me a batch of Lapua and Nosler on Tuesday. $.20 cents each. Not bad prices. The L R brass weighed very consistent. Way better than my Hornady brass. Primer pockets were super tight. Finally found some br2 primers today also. Been looking since we first started reloading.